DENVER — Like the good drug dog he's trained to be, Vader barks and scratches the Chevrolet Suburban's running board when he smells a bag of marijuana hidden between the doors.
Yet the mission for the 80-pound Belgian Malinois is unclear now that Coloradans 21 and older can legally possess as much as an ounce (28 grams), of marijuana. Several new dogs on his 10-member K-9 team won't be trained to sniff out weed while some, like Vader, will keep trying to nose out the drug.
"There are so many unanswered questions," said Colorado Springs police officer Andrew Genta, the K-9 unit's head trainer. "There have not been any test cases to say yes or no we do not have the right to do this."
With new laws that aim to treat marijuana possession much like that of alcohol, law-enforcement agencies in Colorado and Washington state are grappling with whether they should retrain their drug-sniffing dogs to ignore marijuana, retire older pooches who alert when they smell the drug, obtain new animals, or make no changes to their programs.
One issue is whether police can continue to use dogs trained to find pot without violating citizens' rights, in an environment in which marijuana is legal under state law. Officers are also concerned that defense lawyers may use evidence found by such dogs to their advantage in court.
"What's going to come up is a case where a dog hits on a car with two pounds of cocaine," said Sal Fiorillo, tactical operations lieutenant of the Colorado Springs Police Department's Specialized Enforcement Division.
"The defense attorney will say that the dog wasn't hitting on the cocaine, he was hitting on a half-ounce of marijuana, and that's legal," he added. In such a scenario, the lawyer may try have the evidence suppressed because the dog can't differentiate between cocaine and marijuana.
A survey of the largest cities in Colorado and Washington found that K-9 units' responses to legalization measures approved by voters last November vary as much as the breeds of dogs on their teams.
Some police departments won't use animals that were trained to smell marijuana, Fiorillo said, adding that Colorado Springs' K-9 unit will continue to use dogs like Vader based on advice from the local prosecutor.
A month ago, the Colorado District Attorneys' Council started traveling around the state to instruct police officers that a drug-sniffing dog reacting to the smell of marijuana isn't enough for probable cause, said Tom Raynes, the council's executive director.
"The issue is they could be hitting on a legal quantity," Raynes said.
In Washington, the state's Association of Prosecuting Attorneys wrote in a Dec. 4 memo that an officer seeking a search warrant based in part on a dog's alert must disclose the canine's previous training.
The memo, written by Pam Loginsky, the association's staff attorney, recommends that search warrants based in part on a canine trained to detect marijuana include when the dog was trained. She also suggested listing what odors it's trained to detect, that it "cannot communicate which of these substances s/he has detected" and that the dog "cannot communicate" the amount of the substance that's present.
The Washington State Patrol won't train new dogs on its canine team to sniff for marijuana, said Bob Calkins, a spokesman.
"In the past it used to be, if a dog alerted, that was probable cause for a search warrant," Calkins said. "Now, along with the dog's alert, we have to have an indication that there's reason to believe it's something other than marijuana."
Indicators that provide probable cause for a search can include visible signs of other drugs, such as tools used for smoking methamphetamine like a bent, burned spoon, Calkins said.
There's disagreement among departments in Washington and Colorado whether dogs can be taught to disregard an odor once they've been drilled to hunt out the scent for years. The animals give the same alert to all drugs they're trained to find, including cocaine, methamphetamine, marijuana and heroin.
"Once you put an odor on a dog, it's very difficult to get that odor off a dog," said Fiorillo, the Colorado Springs officer. "We can't train our dogs to bark if it's cocaine, roll over if it's marijuana, scratch if it's methamphetamine."
The Seattle Police Department is no longer training its dogs to recognize the odor of marijuana, said Sgt. Sean Whitcomb, a spokesman.
"There's constant training to make sure their sniffers are up to snuff where we use real drugs from evidence and a dog is rewarded for sniffing it out," he said. "Marijuana is not something they are training on -- that skill is no longer being reinforced."
Police in Tacoma, Wash., about a half-hour drive south of Seattle, aren't doing anything differently with their drug-sniffing dogs, which are trained to detect seven different odors, including marijuana, said Officer Loretta Cool.
"There are several instances where marijuana is still illegal, if you are under 21 you cannot possess marijuana," Cool said. "If you have more than an ounce, it's illegal."
In Colorado, the Denver Police Department isn't making any changes to its K-9 program, given that marijuana is still illegal under federal law, said Sonny Jackson, a spokesman. Neither are police in the city's largest suburbs, including Aurora and Lakewood.
"They still use marijuana to train the dogs," said Steve Davis, a Lakewood police spokesman. "If a dog hits on marijuana, you don't know whether you're going to find one ounce in that suitcase or six pounds."
The conflicting views at police departments in Colorado and Washington over whether the legalization of cannabis requires a new way of thinking about how they train their K-9 units may ultimately be resolved by judges.
"The federal courts said a dog's nose is special, it doesn't fall under the regulation of the Fourth Amendment," which prohibits unlawful search and seizure, said Mary Fan, who teaches law at the University of Washington in Seattle.
"In Washington we have a more protective constitution and we said even if that's so under federal law, we think it's intrusive to have a dog walk up and sniff our stuff," she said. "This just adds yet more layers of complexity to the already existing debate as to how much we want to regulate the use of sniffer dogs."